Technical Megasquirt

[arc]

my car is a high compression (skimmed to max markers) n/a. not sure it'd agree with a turbo's ignition table. but once i've turbo'd it i can see them coming in handy. ta.

 

[gazzaman2k]

im stil waiting for a reply from the geezer who builds them still not gave me a date in which itll be ready

 

[randomizered]

Who is building it for you?

 

[davethetrike]

im stil waiting for a reply from the geezer who builds them still not gave me a date in which itll be ready

Bill? Usually pretty good?

Remember you are not dealing with a large firm who hold massive stocks.
They are just interested parties who sell them built, I think mine took around 3 weeks to arrive from initial enquiry to delivery.

Also, each one is different So each one is built to order.

Spend some time reading up on what to expect.

 

[Asteris]

Not much of a difference i'd say. V3.0 PCB is a must and then, it's either MS1 or MS2 processor. All rest are the same, wasted spark with two VB921 outputs, VR rev sensor circuit and either one or two injector banks, depending on 8V or 16V (although you can drive different banks on 8V too, if you run a second cable to inj # 2 and 3.

Arc, i mentioned it's a turbo version table, you can run the stock table with minor mods for high CR (opposite than ours that is, more retard than stock).

 

[randomizered]

OK,

I'm not going to use that stepper motor driver linked as it doesn't seem ready to use yet, and I defiantly want an idle control of sorts

Therefore I'm going to pick up and idle control valve, 2 or 3 wire, not sure which one, model etc.

More importantly though, how do they fit, as I've never messed with a car that has one

I presume that one end links into the Air intake somewhere, but what happens to the other end? It is just exposed to air? has a filter? or is it linked up to somewhere else, like the Air intake, before the butterfly, but after the filter?

Cheers for all your help

Kristian

 

[davethetrike]

Not much of a difference i'd say. V3.0 PCB is a must and then, it's either MS1 or MS2 processor. All rest are the same, wasted spark with two VB921 outputs, VR rev sensor circuit and either one or two injector banks, depending on 8V or 16V (although you can drive different banks on 8V too, if you run a second cable to inj # 2 and 3.

QUOTE]

All the same then

 

[davethetrike]

OK,

I'm not going to use that stepper motor driver linked as it doesn't seem ready to use yet, and I defiantly want an idle control of sorts


I presume that one end links into the Air intake somewhere, but what happens to the other end? It is just exposed to air? has a filter? or is it linked up to somewhere else, like the Air intake, before the butterfly, but after the filter?

Cheers for all your help

Kristian

You answered your own question All you're trying to acheive is a controlled air bypass round a closed tb. Essentially bleeding some air into the intake to aceive a reasonable mixture. So:

out before the intake
past the tb and in the other side of the tb
a valve (by whatever name) passes some air through

Its been tried with mixed success - try a google search its surprising what is buried in other forums.

 

[Asteris]

MS-II IAC stepper control does not have any problem controlling idle, apart from rare irregularity that goes away when turn off and on again.

AND, closed loop idle mode is on its way, just like stock ECU, all you define is idle revs at certain coolant temp on a table...

 

[Asteris]

Thank you I'll try again on Friday

I thought 17 teeth was too many but you say 20 , again I'll check on Friday

Is yours running OK?

Love your optimism with line 4

Found out yesterday about that. There is a small port on the gearbox, which shows 0, 5, 10 and 15 degrees timing marks. Borrow a timing pistol, set Fixed Advance at Fixed Timing (at More ignition options) and Timing for Fixed Advance at 10 degrees.

Then, you can start your engine and check what the gearbox port shows, and if necessary, go at Tools -Trigger wizard and set the correct value. If the value is more than +/- 6 degrees, change a tooth (or angle) at Trigger wheel settings.

 

[davethetrike]

Found out yesterday about that. There is a small port on the gearbox, which shows 0, 5, 10 and 15 degrees timing marks. Borrow a timing pistol, set Fixed Advance at Fixed Timing (at More ignition options) and Timing for Fixed Advance at 10 degrees.

Then, you can start your engine and check what the gearbox port shows, and if necessary, go at Tools -Trigger wizard and set the correct value. If the value is more than +/- 6 degrees, change a tooth (or angle) at Trigger wheel settings.

Good thinking! But mine hasn't got that - I noticed it was missing when I put the gearbox in.
Was using megasquirt with my supercharged today

 

[davethetrike]

LC 1 Lambda connections.



I'm getting more than a little confused about how this is wired.

Brown goes to what pin on the megasquirt



Pin 23 I suppose?


So what happens to the original black wire from my narrowband sensor? Currently this feeds back to the ecu but gives a signal to my afr meter
Arghhh electrics!

 

[randomizered]

The LC1 has two analogue outputs.

You need to check the voltage range of your gauge and configure output two to swing between these two voltages..or less if you want more sensitivity.

Output one will go to pin 23 on the MS. As I understand , MS will only deal with 0-1V input, so set output one of the LC1 to 0-1V as well.

If MS can handle 0-5v outputs, then configure the LC1 that way.

you can link the black wire for your gauge to output two...no need to replace the wires.

You will then ONLY need the WB lambda and can ditch the narrow band entirely.

Make sense?

Kristian

 

[arc]

make sure you ground the LC1 and MS at the same place.

Do not ground the LC1's heater ground to the same point though.

 

[davethetrike]

The LC1 has two analogue outputs.

You need to check the voltage range of your gauge and configure output two to swing between these two voltages..or less if you want more sensitivity.

Output one will go to pin 23 on the MS. As I understand , MS will only deal with 0-1V input, so set output one of the LC1 to 0-1V as well.

If MS can handle 0-5v outputs, then configure the LC1 that way.

you can link the black wire for your gauge to output two...no need to replace the wires.

You will then ONLY need the WB lambda and can ditch the narrow band entirely.

Make sense?

Kristian

Yes but....
The spi (mpi the same just different colours) has a black (mpi yellow and black) and yellow (mpi red blue) to the ecu. Now which of these carries the signal to the ecu. On my standard ecu I t into the black to get a signal at the afr meter (narrowband). So what should I connect the wideband 0 to 5vs to? Which of these carries the signal?

 

[randomizered]

Afraid I don't have the punto manual, well, not working anyway.

The lambda is a 4 wire lambda? One wire is 12V (light blue/white), one is earth (black/blue), screening (black), then you have two for the sensor output, both shielded.

On the spi sei, the signal is pin 29 on the ECU, colour is G on the schematics (yellow).....pin 12 H (grey) is referenced earth.

So link the output of the LC1 to pin 29, and pin 23 to earth.

If you are just using the MS ECU, you don't need to worry about the referenced earth by the looks of it, prob just uses another earth.


not sure if thats any help?

Kristian

 

[Asteris]

Set LC1 to output NB signal at Analogue1. Then connect Analogue1 directly to stock ECU pin 29. Cut the cable off an old NB sensor and connect through it (usually the black wire). This way A/F meter and stock ECU (if ever is fitted again) will see the expected 0-1V signal.

Analogue2 goes directly to MS pin23. Set MS to LC1 Wideband (Configurator, Basic setup-EGO control and Tools-Calibrate AFR table).

 

[davethetrike]

Set LC1 to output NB signal at Analogue1. Then connect Analogue1 directly to stock ECU pin 29. Cut the cable off an old NB sensor and connect through it (usually the black wire). This way A/F meter and stock ECU (if ever is fitted again) will see the expected 0-1V signal.

Analogue2 goes directly to MS pin23. Set MS to LC1 Wideband (Configurator, Basic setup-EGO control and Tools-Calibrate AFR table).

:bang: Of course, I can connect straight to the megasquirt:bang: when the megasquirt isn't connected it won't matter and when it is it is fine...how did I miss it!

I got this strange idea about using the original lambda connector and leaving things so I could just swap them round soldering this and cutting that. When all I need is straight to the squirt It's so obvious its funny
Ah well, another few hours with the iron

 

[Asteris]

Ok, here is my initial idea on the MS harness.

MS will be installed under passenger dashboard. Harness will be routed through the firewall and then to the dummy ECU to the left.

Wires will be connected to the dummy case through din connectors, one for injectors-coils, one for power-fuelpump-ground-+5V, one for TPS-CLT-IAT-Baro-tach signal, one for IAC-boost-knock and one 10-wire for future connections. Din connectors will be connected inside the dummy case to the 35-pin Magneti Marelli connector, so everything stays stock from there on.

There is also an extra din connector to the side, which will be used as output to the knock sensor, boost control and 2nd injector bank.



P.S. Why is the forum optimized for 800 pixels screen width? Does any of the admins realize that we are at 2007?

 

[davethetrike]

Update

(Very tidy Asteris )

Most of the stuff is done on the Punto now so its now down to tuning the MS. I know zilch about this so 'scuse me if I get it wrong. Wideband now connected (LC1)
and I'm using AFR target settings. 226cc (Marae 1.8 injectors -iwp006) being used. These are a straight swap for the standard 16v - iwp045 200cc injectors. I'm running NA at the mo.

Car was unwilling to start on the MS but did - it sounded very rich to my ears. The AFR was 10.03 at 1100 revs kpa around 48. Hesitation on acceleration. So very rich. I adjusted the injector constant value in small steps from 9 to 7. At around 8 the wideband started to take effect and pulled the mixture to 13.03 to one. You know the wideband is working because it has a warm up, the light blinks for 20 secs, after this period the mixture was magically pulled from overich at around 11:1 to 13.03 to one. As I shortened the injector duration so the mixture weakened, but the wideband pulled it in.....as long as the constant duration wasn't way out. As I weakened it so I lost the good idle and it started hunting. In 45 minutes I had good mixture right through the rev range Although I'm still not to happy with the idle.

But, the engine overheated:bang: Which it would because the standard ecu controls the fan an MS doesn't A little more wiring to do.......
PS I know this is the cinq area and I have a Punto so send me a pm if you would prefer I didn't post here and I'll pop it in my scharged thread. Seems more relevant here though